Invertible topological defects of codimension
one, or domain walls, are closely related to symmetries of the field theory [1]}. Given a symmetry we can construct a topological
domain wall which acts on fields passing through it by applying the symmetry.
On the other hand, one can recover the action of the symmetry on fields by wrapping the defect around
a field insertion. The description of symmetries and their
corresponding background gauge fields via topological domain walls makes it possible
to describe their action on other quantities of the quantum field theory such as boundary conditions
or other (non-topological) defects [2]}.
